Structures, such as those found on aircraft and spacecraft, are often subject to stresses that may cause cracking in such structures. Left unchecked, such cracks can grow to critical length and cause loss of structural integrity. For example, a wing of an aircraft, which is subject to flexing up and down throughout every flight the aircraft makes, may develop cracks typically running in the fore-aft direction perpendicular to the tension load direction. Such cracking may affect structural integrity resulting in a weakening of the wing. Federal and military regulations require that such structures be designed to the point of being “fail-safe” for the maximum loads expected in any flight. As a result, aircraft that might be deemed very safe even with some cracked components might nonetheless be precluded from flight until the cracked components are repaired. The processes of finding small cracks and equipping every airport to fix every possible structural component of every aircraft may be difficult and expensive. Accordingly, it is desirable to create structures that are capable of retarding cracking to minimize any loss of structural integrity until proper maintenance can be performed.